The portrait of a dashing young man, Dario was the heir to the Einlanzer after Garai. Born to the legendary fighter, Dario was trained in the tradition of the Acacia Dragoons, practicing long and hard in combat and physical training. He lived in a shack in Termina with his brother Glenn, leading to some feelings of inferiority due to their humble conditions. Regardless, Dario trained well and developed a friendly competition with Karsh. Dario, Glenn, and Karsh often entered the Viper Tournament of Swords; Dario placed first with regularity. He also had an eye on General Viper's daughter, Riddel; he gained her admiration by serving as an upright and noble Dragoon, set to lead an illustrious career as a magnificent knight. He also shared a love of Bellflowers; Riddel would often pick them in Fossil Valley under Dario's watchful eye. Dario finally proposed to her in 1017 A.D. by giving her his family heirloom, the Memento Pendant; Riddel agreed to marry. Unfortunately, Dario was set to go on an expedition to the Isle of the Damned with the other Dragoons soon after; while there, he found the demonic Masamune and was consumed by it. He was able to hold back from killing Karsh long enough to afford Karsh the chance to take a swing at him in turn; Dario was slain by Karsh's blow. Riddel and Glenn mourned for him; he was publicly venerated in Termina.

However, in Home World, Dario somehow survived Karsh's blow and drifted to the Forbidden Island, where he was found by Dario's Caretaker, a caring woman who nursed him back to health. Meanwhile, the Acacia Dragoons ventured to the Dead Sea and perished, while Viper Manor fell into ruin. The incident gave Dario chronic amnesia, and he remained under her care for the next three years. In 1020 A.D., he encountered Serge and the other Acacia Dragoons, who visited the island. They struggled to jog his memory, eventually bringing Riddel and the Memento Pendant. This successfully caused him to remember the past, but at the expense of his knowledge of the Masamune returning. The Masamune came to him, and he violently attacked the party, who narrowly defeated him in battle. Dario subsequently was released from its grasp; he apologized to his Dragoons, and went with them to the ruined Viper Manor. By Riddel's wishes, he stayed there to officiate its rebuilding; it eventually turned into an orphanage, and Dario did well to ensure the children a good life.

Missing Piece translations (see images below)

It's hard to tell in-game, but Dario is actually quite tall. Is this due to his Garai blood?

The epaulets on Dario's armor are big, differentiating him from Karsh.

Perhaps due to our (too?) strong desire to make the leader of the Acacia Dragoons a large figure, Dario gives off a rather amusing impression of a middle-aged fellow.

He looks more like a samurai than a knight? With his slender sword, Dario has an uncanny resemblance to a samurai.